All you can do is try. Nobody can say for sure whether your system will be stable if you overclock it. All they can do is give suggestions for you to try. If it's not stable, you can always lower the settings until you find a spot where it is stable.
However, since your processor isn't even running at the stock speed, bumping it to 166fsb won't be overclocking. Right now, you are underclocked. Set it to 166 and boot back up. After that works out, then worry about overclocking.
And yes, the clock multiplier will be under the fsb setting in the bios.